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COMPOSITION OF AIR, , |, , 1, , @ NITROGEN, m OXYGEN, @ OHER GASES

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i,, , Kuss IS AIR POLLUTION ;, , « The contamination of air with harmful,, unwanted substances which have harmful, effects on both living and non-living objects, is called air pollution., , « The harmful and unwanted substances :, causing air pollution are called air, pollutants.

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~~ The substance which contaminate th, ~~are called air pollutants. Sometimes,, such substances may come from natural, sources like smoke and dust arising from, forest fires or volcanic eruptions., Pollutants are also added to the, mosphere.by certain human activities., , The sou pollutants are — —, , power plants, automobile, , exhausts and burning of firewood and, dung cakes.